text: Wastewater treatment plants may be distinguished by the type of wastewater to be treated. There are numerous processes that can be used to treat wastewater depending on the type and extent of contamination. The treatment steps include physical, chemical and biological treatment processes. 
  Types of wastewater treatment plants include:
  * Sewage treatment plants
  * Industrial wastewater treatment plants
  * Agricultural wastewater treatment plants
  * Leachate treatment plants